Universal logical operations on cat codes

July 21, 2017

In collaboration with Rob Schoelkopf’s group, our paper on implementing universal gate set on a logical qubit encoded in an oscillator is published in Nature Commun.

Based on our earlier theoretical investigation [PRA 92, 040303 (2015)], we demonstrated universal control of the circuit QED system in the strong dispersive regime, which enables us to achieve universal logical operations over bosonic quantum error correcting codes. Here we demonstrate a holistic control strategy which exploits accurate knowledge of the Hamiltonian to manipulate a coupled oscillator-transmon system. We use this approach to realize high-fidelity (98.5%, inferred), decoherence-limited operations on a logical qubit encoded in a superconducting cavity resonator using four-component cat states. Our results show the power of applying numerical techniques to control linear oscillators and pave the way for utilizing their large Hilbert space as a resource in quantum information processing.

External link: https://www.nature.com/articles/s41467-017-00045-1